It's not easy in that situation. But I'd encourage you think outside the box.

Commandeering a local council planter, sticking a raised bed in the odd car park here and there could be an optiion. As could access to a flat roof.

Check out if there is a guerilla garden group in your area. Every % counts.

Even if its herbs grown on a balcony or sunny window.

I start, grow on and sell herb plants on e-bay in a gow tent in my spare room.

I was able to buy £1,500 worth of #bitcoin last year.. at £20-40k 😃

Basicly my point is don't limit yourself to "i can't", but liberate yourself with "how can i".